Process of preventing the oxidation and deoxidation of copper when heated



(No Model.)

' G. W. CUMMINS.

FROCBSS OP PRBVENTING THE OXIDATION AND DEOXIDATION OP COPPER WHEN HEATED.

No. 429,892@ Patented June 10, 1890.

UNITED STATES PATENT GEEICE.

GEORGE VVYCKOFF CUMMINS, OF VIENNA, NEV JERSEY.

PROCESS OF PREVENTING THE OXIDATION AND DEOXIDATION OF COPPER WHEN HEATED.

SPECIFICATION forming part of Letters Patent No. 429,892, dated June 10, 1890.

Application tiled August 15, 1889. Serial No. 320,798x (No model.)

To all whom it may concern:

Be it known that I, GEORGE WYCKOEE CUMMINs, of Vienna, in the county of Varren and State of New Jersey, have invented a new and'useful Process of Preventing the Oxida tion and Deoxidation of Copper when Heated or beingAnnealed, which invention is fully set forth and illustrated in the following speciiication and accompanying drawing.

The object of this invention is sufficiently indicated by its title above given.

The invention will lirst be described in detail, and then particularly set forth in the claims.

The drawing illustrates in sectional side elevation an apparatus suited to carry out the process.

In said drawing the several parts are indicated by let-ters of reference, as follows:

The letter A indicates a retort, preferably of iire-clay lined with copper a; B,a heatingfurnace for said retort provided with a chimney H; C, a tank or receptacle for holding water or other cooling-liquid; D, a closed passage leading from the retort A to the liquid in said tank; E, an inlet-pipe for steam 5. F, the cover or door of the retort A 5 and G, an openinginto the passage D and retortAfortheinsertion of a proper instrument or tool for drawing the articles of copper heated in the retort A from said retort to the passage D, whence they fall into the liquid in the tank C.

As is well known, copper o1' any alloy of copper when heated to redness in the presence of free oxygen readily oxidizes, and there is formed upon its surface a coating or copper scale-a black oxide of copper-Which is very undesirable, owing to the direct loss of copper and to the difficulty and expense of its removal when necessary to be effected in order to obtain clean copper; hence the object of this invention is to prevent the formation of said oxide in the operation of annealing copper or its alloys. This is effected in the apparatus hereinbefore described in the following manner: The tank C is supplied with liquid until it rises a few inches above the opening into the passage D. The retort A having been heated by the furnace B, steam from a boiler or any suitable source is let in at E under sufficient pressure to cause the expulsion of the air contained in the retort A out through the liquid in the tank C. When all said air has been replaced by steam, the door F may be opened and the copper pieces or articles to be annealed placed in the reitort A. The door F being then closed, the copper yis allowed to become heated in the retort,- -`steam in the meantime being continuously passed therein at E. When the copper has attained the required temperature, a hook or other conveniently-shaped rod or tool is inserted through the opening G, by which the articles of copper are drawn through the passage D,Whence or through which they fall into the liquid in the tank C, in which the operation of annealing is completed.

Steam of but moderatepressure may be employed, which will be superheated by the heat supplied to it while passing through the retort A.

Marked advantages of this process are that even very line copper wire may be produced of exactly uniform diameter in any desired quantity. Vhen once oxide has been permitted to form, its removal entails great uncertainty as to the exact-diameter of the iinished wire. Large quantities of copper Wire are now in constant demand for winding electro-magnets and such uses, the requirements being that the wire shall be exact in diameter, even to the one-thousandth of an inch or less. This process also prevents the deoxygenation of the copper which reducing-gases effect, thus ruining the copper, all so-called pure copper having normally oxygen in its composition, according to the best authorities, the removal of which oxygen renders the copper brittle, and which brittleness subsequent annealing will not remove. lf the removal of this oxygen Only resulted in leaving metallic copper, no harm would happen; but the fact is that owing to the presence of oxides of some foreign metal-commonly such as arsenic and antimony-t-he release of their oxygen leaves them in their metallic state, in which condition they ruin the copper, whereas if preserved in the state of oxides they exert no appreciable deleterious influence. These foreign substances or impurities are present in electro-deposited as well as other commercial copper.

IOO

Itis obvious that the process may be ei'- fected in other forms of apparatus. Idonot, therefore, conine the process to the special form of apparatus herein described.

Care should be taken not to leave the hole G open longer than is necessary to perform the required manipulations with the rod introduced through it. The passage D may be lengthened somewhat, if desired, so as to permit the copper to part with some of its heat before reaching the liquid in the tank C. A peephole closed with mica may be fitted in the retort A, if desired, through which the heating of the copper can be observed and its degree of heating ascertained with sutlieient accuracy by theeye. This process may be likewise usedin auncalin g alloys of copper.

Itis obvious that the liquid seal between the retort A and tank C is a simple and most efiicient means for accomplishing the air exclusion desired, yet other well-known air seals or valves may be substituted to aecomplish the same result as the Water seal shown. Oil or other cooling or annealing liquid may be substituted for water, if desired, Without departing :from this invention.

Having thus fully described my said process and apparatus as of my invention, I claiml. The process of preventing the oxidation ot' copperand its alloys when heated to a temperature suilicient to cause oxidation if ex posed to the presence of atmospheric air, consisting in inclosing the same before reaching and While at such temperature in an atmosphere of steam, thereby excluding' said air, substantially as set forth.

2. The process of annealing copper and its alloys, consisting in rst heating the same While inclosed in an atmosphere of steam to a temperatu re sufficient to cause oxidation if exposed to atmospheric air, and then cooling in Water or other cooling medium without access ot' air, substantially as set forth.

3. In annealing copper and its alloys, the process of inelosing the same in an atmosphere of steam to the exclusion of atmospheric air and heating the metal in the presence of said steam to the desired temperature before cooling, whereby both deoxygenation and oxidation of the metal are prevented, substantially as and for the purposes set forth.

G. WYCKOFF CUMMlNS.

Witnesses: y

FRED F. KAZANBACH, JOHN '.l. SILER. 

